The following corrections were implemented for the revised copy of GOTV IV:
*We are deeply grateful to Christopher Mann whose careful replication led to 
these corrections*

Vote.org (Gold et al. 2017) study has now been included in the meta-analysis.
Amended a transcription error on the Panagoupolos (2007) study.
Amended a transcription error on the Broockman et al. (2017) study.
Malhotra et al. (2011) studies have been treated as separate rows of data instead of being 
collapsed due to be consistent with the coding decision discussed in the book.
Ternovski et al. (2013) studies have been treated as separate rows of data instead of being 
collapsed due to be consistent with the coding decision discussed in the book.